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81.
82.
Normal and diseased superficial digital flexor tendons at different stages of healing from seven Thoroughbred horses, aged 3–6 years, were evaluated by correlation of gray scale histogram analysis of tendon cross-sectional ultrasonograms with histopathologic examination. Normal tendon and tendons at different stages of healing, excluding acute tear stage, were characterized by normally distributed histogram patterns. The histogram mean value of normal tendons was higher than the corresponding values in diseased tendons at different stages of healing (p < 0.01). In addition, the histogram mean of acute lesions was lower than for early fibrosis or healed lesions (p < 0.01). The histogram mean increased as healing progressed. The results show that gray scale histogram analysis of tendon ultrasonogram can be used to distinguish between normal and abnormal superficial digital flexor tendon in racing horses.  相似文献   
83.
In microorganisms, menaquinone is an obligatory component of the electron-transfer pathway. It is derived from chorismate by seven enzymes in Escherichia coli. However, a bioinformatic analysis of whole genome sequences has suggested that some microorganisms, including pathogenic species such as Helicobacter pylori and Campylobacter jejuni, do not have orthologs of the men genes, even though they synthesize menaquinone. We deduced the outline of this alternative pathway in a nonpathogenic strain of Streptomyces by bioinformatic screening, gene knockouts, shotgun cloning with isolated mutants, and in vitro studies with recombinant enzymes. As humans and commensal intestinal bacteria, including lactobacilli, lack this pathway, it represents an attractive target for the development of chemotherapeutics.  相似文献   
84.
Objective To describe the effect of injection volume and anatomy on the spread of new methylene blue (NMB) injected into the epidural space between the first and second lumbar vertebrae in cows. Study Design Prospective experimental study. Sample Population Thirteen nonpregnant cows. Methods Cows were randomly assigned to two groups. Group 1 received 5 mL and Group 2 received 10 mL of 0.12% NMB in 0.9% saline. The injection was made into the first interlumbar epidural space using a dorsal approach. The extent of cranial and caudal migration of the dye, as manifested by the staining of the epidural fat and dura mater, was measured. Results Mean ± SEM number (range) of stained vertebrae was significantly greater in the 10‐mL group than in the 5‐mL group, 4.4 ± 0.6 (T11 to L5) and 3.0 ± 0.2 (T12 to L3), respectively (p < 0.05). Linear regression analysis showed that the volume was significantly correlated with the number of stained vertebrae (R2 = 0.42, p = 0.016). In the dorsal and lateral aspect of the spinal cord, there were two types of distribution of NMB along the surface of the epidural fat: between the periosteum and epidural fat; and between the epidural fat and dura mater. Migration under the spinal cord occurred along the two longitudinal epidural veins. Conclusions and Clinical Relevance The larger the volume of solution injected into the first interlumbar epidural space, the greater the spread. Intrinsic anatomic factors, such as characteristics of epidural fat and veins, influence the epidural spread of injected solution and, consequently, epidural analgesia.  相似文献   
85.
Rather greater variations in the cation exchange capacity (CEC) value of Allophane, say, 20 to 100 me per 100 g of clay (1), have been reported by a number of investigators. BIRRELL and his collaborators (5, 6) revealed that the CEC of allophane depends on concentration and pH of a leaching solution, kinds of cation and anion, volume of washing alcohol, and its water content. The results suggest the peculiarity of allophane in ion-exchange phenomena.  相似文献   
86.
Phenolic acids in rice straw and its decayed product were surveyed and quantitatively analyzed by gas chromatography.

1) Thirteen kinds of phenolic acids in rice straw and its decayed product were identified. Besides p-hydroxybenzoic, vanillic, P-coumaric, and ferulic acids which had been already reported, nine phenolic acids were newly identified; these were benzoic, salicylic, syringic, protocatechuic, β-resorcylic, caffeic, sinapic, gallic, and gentisic acids.

2) A gas chromatographic analysis was applied to the micro-determination of major phenolic acids in rice straw and . the decayed products. The methanolic alkaline extracts from them were washed with ether, acidified, transferred into ether, trimethylsilylated, and injected into a gas chromatograph equipped with a silicon SE-30 column. The recoveries of p-coumaric, p-hydroxybenzoic, vanillic, and syringic acids were more than 90%, and ferulic and syringic acids were recovered at about 70%.

3) The content of each of the above described major phenolic acids in rice straw ranged from 0.002 to 0.037% per dry weight. p-Coumaric acid was contained in the largest amount. Ferulic and vanillic acids followed. In the decayed straw, these contents decreased to 0.002–0.017%. The whole phenolic substances in ether-extracted fraction were present at 0.34%, and the amount decreased to one-third during the decaying process.  相似文献   
87.
A model experiment was carried out at 15, 25, and 35°C to investigate the changes in microbial biomass and the pattern of mineralization in upland soil during 8 weeks following the addition of 8 organic materials including 6 tropical plant residues, ipil ipil (Leucaena leucocephala), azolla (Azolla pinnata), water hyacinth (Eichhornia crassipes), dhaincha (Sesbania rostrata), cowpea (Vigna unguiculata), and sunhemp (Crotalaria juncea). The amounts of CO2-C evolved and inorganic N produced at 35°C were about 2 times larger than those at 15°C. At any temperature, the flush decomposition of C was observed within the first week and thereafter the rate of mineralization became relatively slow. A negative correlation was observed between inorganic N and C/N ratios of the added organic materials. The relationships between the amounts of cellulose or cellulose plus hemicellulose and the amount of mineralized N of the added organic materials were also negative.

The changes in the microbial biomass were affected by temperatures. The amount of biomass C and N was maximum after 42 d of incubation at 15°C, and after 7 d at 25 and 35°C, and thereafter decreased. The rate of biomass decline was slower at 15°C and faster at 35°C than at 25°C. Regardless of the temperatures, the addition of organic materials enhanced microbial biomass formation throughout the incubation periods.  相似文献   
88.
The bacteria from an 800-l carp rearing tank were isolated on five different media during a 45-day experimental period. Total viable counts and the variety of groups of bacteria detected in the water increased after the carp were stocked. The Vibrio-Aeromonas group and Bacteroides type A, which were major components in the intestinal tracts of carp, increased after fish were introduced, and decreased after fish were removed.  相似文献   
89.
The chemical structures of hemicellulose and lignin are different for two distinct types of wood, i.e., softwood and hardwood. Such differences are expected to affect pyrolysis behavior. In this article, the differences are discussed for Japanese cedar wood (a softwood) and Japanese beech wood (a hardwood) pyrolyzed in a closed ampoule reactor (N2/600°C/40–600 s). Oven-dried samples were used to eliminate the influence of initial water. Demineralized samples (prepared by acid washing) were also used to determine the influence of the minerals contained in the wood samples. As a result, some features were disclosed for secondary char (coke) formation, char reactivity, tar formation, and subsequent decomposition.  相似文献   
90.
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